Draculamya porobranchiata
| Draculamya porobranchiata | ||||||||||||
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| Scientific name | ||||||||||||
| Draculamya porobranchiata | ||||||||||||
| Oliver & Lützen , 2011 |
Draculamya porobranchiata is a mussel species from the lentil mussel family(Montacutidae). The species lives parasitically by injuring its victims with a special piercing organ and sucking their body fluid.
features
The flared, flared housing is very small and rarely exceeds two millimeters. It is slightly unequal, with the vertebra slightly behind the midline. It is roughly rounded in outline, only slightly skewed and slightly pulled out at the front. The anterior dorsal margin is slightly longer than the posterior dorsal margin. The comparatively powerful lock has a single cardinal tooth and a posterior and an anterior lateral tooth in the right flap. The cardinal tooth is missing in the left flap, the anterior and posterior lateral teeth are continuations of the edge of the housing. The internally lying ligament sits on a flat resilifer that is slightly crooked between the cardinal tooth and the posterior teeth. The Prodissoconch measures 470–500 µm in diameter; it has a radial microstructure. The two approximately equal muscle impressions are only indistinctly developed on the fresh shell. The anterior sphincter is closer to the anterior margin than the posterior sphincter to the posterior margin.
The shell is thin but firm. The sculpture consists of growth strips parallel to the edge and distinctly different growth interruptions. The periostracum is thin with fine lirae that are most evident on the edge of the case.
The gills consist of a series of pores covered with cilia. Seed bags are available. In contrast, there are no labial palps (mouth lobes). The throat is surrounded by a strong circular muscle. The anterior stomach area is greatly enlarged, and there are no dividers. The foot has a byssus. In the byssus pit on the front foot there is a spike on a bulge that functions as a lancing organ.
Similar Art
The housing of Draculamya porobranchiata is similar to that of the fossil Draculamya pumila from the Pliocene of southern England. The latter species, however, has a crooked egg-shaped outline; it also has a distinct marginal pit, which is most pronounced on the dorsal margins. The Prodissoconch of Draculamya pumila is with 380 to 410 μm significantly smaller than the Prodissoconch of Draculamya porobranchiata with 470 to 500 μm.
Geographical distribution and habitat
The distribution area of Draculamya porobranchiata ranges in the north-east Atlantic from 69 ° N to 44 ° N in water depths of 1100 to 1350 m. Habitat information is currently only available for Porcupine Bay. Here some specimens were dredged from a depth of 1279 m to 1328 m . The hexactinellide pebble sponge Pheronema carpenteri dominates here on the sea floor . Before in this habitat are: the brittle star Ophiactis abyssicola , the crab Dorynchus , pectinide clams , polychaete and sipuncula . Numerous holothuria live in the sediment, especially of the species Ypsilotheria talismani . It is true that echinoderms and sprayworms are often hosts of galeommatid clams . So far, however , Draculamya porobranchiata has not been specifically associated with any of the above species.
Way of life
The development is direct. The eggs are fertilized in the mantle cavity, where they develop into small, young clams.
The descriptive authors assume that Draculamya porobranchiata feeds on body fluids from other marine animals. So far this way of life has not been proven directly. However, the species has a number of anatomical features that suggest this way of life. First and foremost, this is a piercing organ at the front end of the byssus pit. The gills are greatly reduced, and there are also no labial palps; the animals can no longer filter and ingest food from the water flow. The digestive tract is heavily modified. The pharyngeal muscles take the form of a suction pump. The forestomach is greatly enlarged and probably consumed a large amount of liquid food. The main stomach is only slightly separated with a small gastral plate and a pedicel sac. The opening of the diverticula is wide open. The ovary sits in the mantle. (Foreign) sperm are collected on the gills in paired semen prescriptions. There are right and left pericardia that are not fused together. Therefore, as with other mussels, there is no actual heart. Oxygen is supplied through thin walls that separate the mantle cavity and the comparatively very large bulut sinus from each other.
supporting documents
literature
- P. Graham Oliver and Jørgen Lützen: An anatomically bizarre, fluid-feeding, galeommatoidean bivalve: Draculamya porobranchiata gen. Et sp. Nov. (Mollusca: Bivalvia). Journal of Conchology, 40 (4): 365-392. 2011 Online at ResearchGate